River Ithon

The River Ithon is a major left-bank tributary of the River Wye in Radnorshire. It rises in the broad saddle between the western end of Kerry Hill and the hill of Glog to its west and flows initially southwards to Llanbadarn Fynydd. It then takes a twisting route south via the villages of Llanbister, Llanddewi Ystradenni and Penybont before turning south-west, then doubling back northwards towards Crossgates. From here it resumes a south-westerly course, flowing past Llandrindod Wells to a confluence with the Wye, a mile to the south of Newbridge-on-Wye.

The Camddwr is a left-bank tributary of the Ithon. It rises in undulating countryside to the east of Llanbister and flows in a generally south-westerly direction to join the Ithon at Abercamddwr.